Click at upper part of the screen to display the control panel.
Clicking the screen with the control panel displayed will retract the control panel.
Click the lower right corner of the screen to display the full screen button. Click the full screen button to switch between full screen and non-full screen.
Left-clicking on the screen with a Waka is displayed will let the Waka disappear.
Right-clicking on the screen (long touch for touch devices) when a Waka is not displayed will display the Waka.
Right-click on the screen with a Waka displayed (long touch for touch devices), information about the Waka will be displayed.
Click on the screen for the cover page and the last page (credit notation) to go to the next page (the cover page for the last page).